1. Field
Example embodiments relate to distance measuring sensors that include a vertical photogate. Example embodiments also relate to three-dimensional color image sensors that include distance measuring sensors. Also, example embodiments relate to distance measuring sensors that include a vertical photogate formed to a depth in a substrate and three-dimensional color image sensors that include distance measuring sensors.
2. Description of Related Art
A photogate depth sensor may measure the distance to an object by irradiating light on the object and calculating a delay time of light reflected from the object.
A color image sensor is a photoelectric conversion device that may transform detected light into electrical signals. A conventional image sensor may include a plurality of unit pixels arranged in an array on a semiconductor substrate. Each of the unit pixels may include a photodiode and/or a plurality of transistors. The photodiode may detect external light and/or may generate and store charges, and the transistors may output electrical signals according to the stored charges.
A complimentary metal oxide semiconductor (CMOS) image sensor may include a photodiode that can receive and/or store optical signals, and may realize images by using a signal processing device to control and/or process the optical signals. The photodiode may be manufactured in a single chip together with the signal processing device using a simple CMOS manufacturing technique.
A three-dimensional image sensor may realize a three-dimensional color of an object by measuring the color of the object and/or a distance to the object.
A distance measuring sensor has been disclosed in U.S. Pat. No. 6,396,570. However, this distance measuring sensor may include double photogates on a light-incident surface. Thus, the amount of light may be reduced when passing through the photogates and/or a light sensing area may be reduced due to the double photogates, thereby reducing the sensitivity of distance measurement.